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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Methods for reducing vehicular greenhouse gas emissions using electric vehicles and wind-electricity

Kannan, Shanmuga Sundaram 12 July 2012 (has links)
Recently, electric vehicles (EVs) have been gaining attention in passenger transportation due to their greater fuel economy and reduced greenhouse gas (GHG) emissions compared to conventional vehicles (CVs). The amount of GHG emissions reduction from EVs depends on the energy sources used to generate electricity. Wind is a clean, renewable energy source and EVs charged from wind-generated electricity do not produce any emissions. However, wind is variable in nature. This thesis examines the potential impact of EVs on reducing a jurisdiction’s vehicular GHG emissions using locally available wind-electricity. Four methods of charging EVs using wind-electricity are considered, with grid-electricity as a backup, and the overall well-to-wheels GHG emission reductions are discussed. The thesis includes a case study of Summerside. The results show that up to 68% of the EVs’ demands were met with wind-electricity, and Summerside’s vehicular GHG emissions were reduced by between 56% and 73% when compared to CVs.
2

Tracking Emissions Reductions and Energy Efficiency in the Steel Industry

Morfeldt, Johannes January 2017 (has links)
The iron and steel industry has become increasingly globalised. Market conditions are also changing and de-carbonisation of production is challenging. The objective of this thesis is to assess how energy efficiency and greenhouse gas emissions reductions can be promoted and effectively monitored in the steel industry. The thesis contributes with analyses based on the Malmquist Productivity Index for a top-down analysis of the energy efficiency of EU Member States’ iron and steel production, and Partial Least Squares regression for bottom-up assessments of different monitoring tools. The thesis also contributes with a scrap availability assessment module to enhance the energy system model ETSAP-TIAM. The first phase of the research showed that future production needs to shift towards innovative low-CO2 technologies even when all available recycled material is fully used. Techniques using carbon capture and storage (CCS) as well as hydrogen-based technologies can be expected to become economically viable under tightened climate policies. The second phase of the research showed that current indicators are insufficient. System boundaries of energy use and emissions data do not align with production statistics. Indicators based on energy use or emissions in relation to production in physical terms may be useful to track specific processes. However, current indicators fail to reflect the companies’ product mix. Enhanced energy and climate indicators that adjust for the product mix provide better estimates while failing to reflect the increasing globalisation. Effective monitoring of industrial transformation will be increasingly important as pressure from climate policy via global CO2-pricing is unlikely in the short term. Current or enhanced indicators do not fully capture industrial transformation and are not recommended. Future research should focus on defining indicators to estimate energy use and emissions along industrial value chains in climate policy contexts. / Järn- och stålindustrin har blivit alltmer globaliserad. Marknadsvillkoren förändras samtidigt som utfasningen av fossila bränslen är utmanande. Målet med den här avhandlingen är att bedöma hur energieffektivitet och växthusgasutsläppsminskningar kan främjas och effektivt utvärderas inom stålindustrin. Avhandlingen bidrar med analyser baserade Malmquists produktivitetsindex för att analysera energieffektivitet av EU:s medlemsstaters järn- och stålproduktion, och partiell minsta- kvadrat-regression för att bedöma olika utvärderingsmått. Avhandlingen bidrar även med en modul som bedömer skrottillgång för att förbättra energisystemmodellen ETSAP-TIAM. I en första fas visade forskningen att framtida produktion behöver ställas om mot innovativa teknologier med låga CO2-utsläpp även när allt tillgängligt återvunnet material används fullt ut. Tekniker som använder koldioxidinfångning och -lagring (CCS) samt vätebaserade teknologier kan förväntas bli ekonomiskt försvarbara under åtstramade klimatpolitiska styrmedel. I en andra fas visade forskningen att nuvarande indikatorer är otillräckliga. Systemgränser för energianvändnings- och växthusgasutsläppsdata stämmer inte överens med produktionsstatistik. Indikatorer utifrån energianvändning eller utsläpp i relation till fysisk produktion kan vara användbara för att följa upp specifika processer. Nuvarande indikatorer lyckas dock inte spegla företagens produktmix. Förbättrade energi- och klimatindikatorer som justerar för produktmixen ger bättre uppskattningar, men speglar inte branschens ökande globalisering. Effektiv utvärdering av industriell transformation blir alltmer viktig då påtryckning från klimatpolitiska styrmedel via global CO2-prissättning är kortsiktigt osannolik. Nuvarande eller förbättrade indikatorer fångar inte industriell transformation fullt ut och rekommenderas inte. Framtida forskning bör fokusera på att definiera indikatorer som uppskattar energianvändning och växthusgasutsläpp längs industriella värdekedjor. / <p>QC 20170428</p>
3

ESSAYS ON THE ECONOMICS OF MOTOR VEHICLE ENERGY EFFICIENCY

Tingmingke Lu (6689618) 14 August 2019 (has links)
<div>The purpose of this dissertation is to study the effectiveness of public policies in generating fuel savings and emissions reductions. I focus on applying various empirical methods to analyze consumer responses to policy changes on both extensive and intensive margins. This dissertation consists of two chapters.</div><div><br></div><div>In the first chapter, I compare the effectiveness of fuel taxes and product taxes on reducing gasoline consumption of new car buyers. I employ a unified data source for vehicle choice and subsequent vehicle use to estimate a random effects logit demand model that explicitly accounts for vehicle use heterogeneity. My demand estimation suggests that new car buyers fully value the fuel-saving benefits from improved vehicle fuel efficiency when they initially purchase their cars. My policy simulations indicate that high-mileage drivers are more responsive to a change in fuel taxes than to a change in product taxes, even as low-mileage drivers are more responsive to product taxes. By capturing such heterogeneous consumer response to policies, I show that a counterfactual increase of the fuel tax is more effective than a revenue-equivalent product tax in reducing the total gasoline consumption of new car buyers. Further, when accounting for its effects on consumer response on both extensive and intensive margins, a change in fuel taxes has a clear advantage over a change in product taxes in reducing the consumption of gasoline even when the magnitude of tax increase is small. More importantly, a model not accounting for vehicle use heterogeneity understates the fuel saving effects of both policies and misleads us about the relative effectiveness when comparing different policies. </div><div><br></div><div>The second chapter explores how changes in the marginal cost of driving affect consumers decisions about passenger vehicle utilization, as measured by average daily miles traveled per vehicle. This intensive margin of consumer response has important implications for the effectiveness of usage-based policies, such as the fuel tax and the mileage tax, that designed to address externalities of driving. I estimate the elasticity of driving with respect to fuel cost per mile using a large panel data that covers 351 towns and cities in Massachusetts over 24 quarters. While most researchers in this literature apply fixed effects estimators to examine the elasticity of driving, I use a factor model econometric setup to account for unobserved common factors and regional heterogeneity. Residual diagnostics confirm that the factor model setup does a better job of removing the cross-section dependence than fixed effects estimators do. Given low consumer responsiveness to changes in the marginal cost of driving engendered by current usage-based policies, rights-based approaches like congestion charges might be better alternatives to influence vehicle utilization and vehicle ownership.</div>
4

Développement d'une cellule SOFC de type monochambre pour la conversion en électricité des gaz d'échappement d'un moteur thermique / Development of a single chamber SOFC device for electrical energy production from exhaust gases of a thermal engine

Briault, Pauline 16 January 2014 (has links)
Le projet présenté dans ce mémoire a pour objectif de développer un système de récupération d’énergie des gaz d’échappement d’un véhicule à essence. Constitué de piles à combustible à oxyde solide (SOFC) en configuration monochambre, le dispositif doit convertir l’énergie chimique des gaz imbrûlés en électricité. Son fonctionnement en aval du catalyseur trois voies permettrait de compléter son action dépolluante tout en améliorant l’efficacité énergétique du véhicule. Par opposition aux piles SOFC dites conventionnelles, les piles SOFC monochambres ne nécessitent pas de scellement étanche entre les compartiments et fonctionnent sous un mélange gazeux composé d’hydrocarbures et d’oxygène. L’empilement en stack de plusieurs cellules est simplifié et plus compact, son intégration au cœur du pot d’échappement est donc plus simple. Ce concept a été précédemment étudié dans la littérature et le présent projet a pour but d’améliorer les performances délivrées en optimisant certains paramètres : la géométrie de pile et les matériaux d’électrodes et d’électrolyte. De plus, un mélange gazeux plus représentatif des conditions réelles a été défini et utilisé tout au long du projet. Une étude préliminaire sur les matériaux sous forme de poudre a permis de réaliser un premier choix parmi quatre matériaux de cathode et de définir les conditions de fonctionnement théoriques des cellules. Ensuite, les cellules complètes ont été mises en forme puis étudiées sous mélange gazeux. Une densité maximale de puissance de 25 mW.cm-2 à 550°C pour une cellule Ni-CGO/CGO/LSCF-CGO a ainsi pu être obtenue. / This study aims at developing a system able to recover energy from exhaust gases of a thermal engine. Composed of Solid Oxide Fuel Cells (SOFC) in a single chamber configuration, the device has to convert chemical energy of gases into electricity. Embedded in the exhaust line at the exit of the three-way catalyst, the stack of single chamber SOFC will complete the reduction of toxic gases emissions with an improvement of the vehicle energy efficiency.Unlike conventional SOFC, single chamber SOFC do not require any gastight sealing between compartments and work in a mixed atmosphere composed of hydrocarbon and oxygen. Stack assembly is thus simplified and more compact; insertion into the exhaust line is therefore easier. This concept has been previously studied in the literature and this work aims at enhancing performances through the optimisation of some parameters such as cell geometry and cell components materials.Moreover, a more representative gas mixture of actual compositions in the exhaust line has been defined and used all along this project. A preliminary study on the raw materials has allowed to make a first selection among four cathode materials and to define theoretical working conditions of our cells. Afterwards, cells have been elaborated and then studied in the selected gas mixture. A maximum power density of 25 mW.cm-2 has been obtained at 550°C for a Ni-CGO/CGO/LSCF-CGO cell.
5

MARKET ADOPTION AND IMPACT OF ELECTRIC ROADWAYS ON CRITERIA POLLUTANTS AND GREENHOUSE GAS EMISSIONS

Theodora Konstantinou (5930705) 16 January 2019 (has links)
<p>Traffic is inevitably a major source of air pollution, particularly in urban areas. Efforts are made towards reducing emissions by improving vehicle and fuel technology and promoting alternative, sustainable modes of transportation. Although the emergence of EVs has shown capabilities of decreasing energy use and emissions levels, the EV market is developing slowly mainly due to drivers’ range anxiety and charging time. Electric roadways (ERs) have been proposed as a solution to overcome the concerns related to EVs by converting road segments into powered lanes where vehicles can be charged as they move along the roadway. This technology has the potential to increase driving range, decrease battery size and thus, lower the weight and the cost of EVs. In this context, exploring the challenging concept of ERs comes natural. </p> <p>Since data on the market acceptance and the environmental implications on this technology are limited to non-existent, this thesis has the following objectives: 1) identify the factors that affect the short- and long-term intention to use ERs, 2) estimate the level of adoption of the ER technology and identify characteristics of the market segments and 3) assess the impact of ERs on criteria pollutants and greenhouse gas emissions based on the market adoption results.</p> <p>To achieve these objectives, a survey of the general population in Los Angeles, California was conducted, gathering 600 responses representative of gender and age in the area. Los Angeles is considered a leader in electro-mobility and thus, a natural choice for the implementation of ERs. The short-or long-term intentions to drive on ERs and purchase an EV knowing about the availability of ERs were found to be correlated and thus, were modeled simultaneously using a bivariate ordered probit model. The compatibility of the ER technology with respondents’ lifestyle and needs, respondents’ tendency towards using sustainable forms of transportation, respondents’ innovativeness and perceived environmental benefits were among the most significant variables found to affect the short-term and long-term intention to use ERs.</p> <p>The level of adoption of the ER technology and corresponding market segments were identified using a combination of Principal Component Analysis (PCA) and Cluster Analysis. Three clusters emerged from the analysis: early adopters (48.5%), mid-adopters (27.67%) and late adopters (23.83%) that differed in terms of demographics and socioeconomic characteristics, travel and EV charging characteristics and level of awareness. </p> <p>The adoption levels found were then used to estimate the emissions change due to the implementation of the ERs by 2050. Using the California Air Resources Board’s (CARB) 2017 EMissions FACtor model (EMFAC). Two scenarios were examined considering light-duty vehicles (LDVs) in a specific corridor: “with” and “without electrification” scenarios. The results suggested that the ER technology for light-duty vehicles has the potential to provide emission reductions of 4 to 24%. A sensitivity analysis was also conducted to examine the effect of speed on the results.</p> <p>Turning to the practical implications, this thesis can provide a foundational framework for the evaluation of the ER technology in terms of environmental and economic viability and set the groundwork for future research. Ultimately, the short-term and long-term intention analysis can be used as a draft guide by state and local agencies and inform their strategic short- or long- range plans for mobility. By segmenting potential users, policy makers and transport operators can be informed about the main challenges regarding the promotion of the ER technology to distinct market segments and devise ways to accelerate its adoption. The findings from the impact analysis of ERs on criteria pollutants and greenhouse gases can also inform long-range transportation plans and existing regulations and policies in California and beyond.</p> <p> </p>
6

A Foucauldian–Fairclaughian Discursive Analysis of the Social Construction of ICT for Environmentally Sustainable Urban Development – the Case of European Society

Bibri, Simon Elias January 2013 (has links)
ICT has become so deeply embedded into the fabric of European society – in economic, political, and socio-cultural narratives, practices, and structures – that it has been constructed as holding tremendous untapped and inestimable potential for instigating and unleashing far-reaching societal transformation, addressing key societal challenges, and solving all societal problems. It has recently been seen, given its ubiquity, as a critical driver and powerful catalyst for sustainable urban development due to its potential to enable substantial energy savings and GHG emissions reductions in most urban sectors, especially buildings. However, related to this ubiquity, there are also a lot of visions (of limited modern applicability), hopes, myths, fallacies, and oxymora, which applies for the environmental subsystem of information society where debates focus on whether ICT can advance environmental urban sustainability. There are intricate relationships and tradeoffs among the multidimensional effects of ICT for the environment that flow mostly from the use and application of ICT – e.g. energy efficiency technology - throughout the urban sphere. Regardless, the technological orientation and framing of the sustainable city and the green economy has gained dominance in European society and become prevalent in what has come to be identified or known as the discourse of ICT for sustainable urban development (ICT4SUD). The aim of this study is to carry out a critical reading of the social construction of ICT4SUD, the underlying ideology about the ICT potential in advancing environmental urban sustainability. To achieve this aim, a Foucauldian-Faircloughian discursive approach is employed to examine the selected empirical material. This approach consists of nine stages: (1) surface descriptors and contextual elements; (2) historical-diachronic dimension; (3) epistemic and cultural frames; (4) discursive constructions and discourses; (5) social actors and framing power; (6) discursive strategies; (7) discursive mechanisms; (8) political practice, knowledge, and power; and (9) ideological standpoints.As a scholarly discourse, ICT4SUD is inherently part of and influenced by economic, societal, and political structures, and produced in social interaction. ICT4SUD is thus neither paradigmatic nor value-free, but rather socio-politically situated. It is shaped by cultural frames that are conventionalized by European society and attuned to its values, and it is a matter of a pre-intellectual space where ICT and sustainability constitute salient defining factors of the dominant configuration of knowledge, institutions, and material forces of European society. Indeed, ICT4SUD is impacted by earlier representations of reality and how they were reproduced in relation to the significance of discursive constructions of ICT and sustainability issues in the broader context of European culture. Moreover, the ICT4SUD discourse plays a major role in (re)constructing the image of the ICT industry as a social actor and in defining its identity and relation with other constituents of society, in that it is relocated new roles and attributed new societal missions. The dominant framing of the reports is clearly the one advanced by the ICT industry: it is constituted into the main definer of the represented reality. Further, positioning the ICT industry as the driver of the low-carbon city/economy aids the construction of an image of leadership in creating a low carbon society. The reports’ construction of energy efficiency technology is a powerful legitimation of the ICT industry’s views and actions. In addition, the ICT4SUD discourse is exclusionary, namely a number of facts and issues pertaining to structural, indirect, and systemic effects of ICT and the associated rebound effects are left out, concealed, or neglected. Also, the discourse is inclined to be deterministic, i.e. it postulates that ICT, supported by policy, will achieve SUD while it falls short in considering social behaviour and socio-economic relationships. It moreover tends to be rhetorical – that is, it promises environmentally SUD without really having a holistic strategy to achieve that goal. Furthermore, given the scientific discourse and the legitimation capacity of computing, climatology, and sustainability indicators, one can subsume a range of social and political effects under the category of discourse mechanisms through which ICT4SUD operates, which both show the power of discourse and potentially empower the ICT industry and its cohorts. There are different justifications for the development of energy efficiency technology in relation to decision-making processes. Plus, politics, as a consequence of its interaction with ICT4SUD, forces, though different mechanisms, the emergence and development of the ICT4SUD discourse, which is, simultaneously, influenced by the power/knowledge relations established in European society that bounds or expands its success. Finally, as to ideological reproduction, the ICT4SUD discourse reconstructs cultural claims, conveys ideological messages, and reproduces and legitimizes power structures.
7

Sustaining ICT for Sustainability : Towards Mainstreaming De–carbonization–oriented Design & Enabling the Energy–Efficient, Low Carbon Economy

Bibri, Mohamed January 2009 (has links)
The study set out to understand and demonstrate the role the ICT sector could play as a critical enabler in the transition and progress towards an energy– efficient, low carbon economy. More specifically, the study of sustaining ICT for sustainability has twofold intent: (2) to investigate the direct footprint of ICT sector and explore how it can be tackled through adopting sustainable design–based solutions; and (2) to highlight the enabling potential of ICT sector to mitigate climate change and massively improve energy efficiency across the economy, identifying and quantifying the global ICT impacts and opportunities in the context of energy and carbon emissions savings. To achieve the aim of this study, a pertinent and extensive literature review covering theoretical, empirical, and critical scholarship was performed to investigate the phenomenon. The study draws on a variety of sources to survey the unsustainability of ICT sector pertaining to energy–intensive consumption and explore potential solutions through espousing environmental design practice, and also to examine the role of ICT in delivering energy–efficient solutions through its products and services. Validity was ensured through using quality academic and industry literature as well as relevant studies carried out by a range of eminent researchers, experts, and stakeholders (i.e. NGOs, research centers). Findings highlight the unsustainability of ICT sector regarding energy– intensive consumption and concomitant GHG emissions associated with its products and services. Of the whole lifecycle, the use phase of ICT is the most critical. Data centers and telecom networks devour energy. Planned obsolescence entrenched in software design shorten upgrade cycle, which makes software utilities a planet killer as to energy consumption. Alternative sustainable design–based solutions entail using renewable energy and most efficient energy required over ICT’s life cycle – de–carbonization strategy. Also, digitization is an effective strategy for ICT sector to slash energy use per unit. To reduce the footprint of data centers and telecom networks, design solutions vary from hardware and software to technological improvements. Designing out built–in obsolescence in software technology is a key factor in the energy equation. As for the enabling role of ICT, the findings are highly illuminating. The ICT sector must step up its efforts in reducing its direct footprint in order to claim a leadership role in an energy–efficient, low carbon economy. Although the ICT sector’s own emissions will increase because of global growing demand for its products and services, the real gains will come from its enabling potential to yield substantial energy efficiency improvements and emissions reductions across the economy. The sheer scale of the climate change challenge presents smart development mitigation opportunities for ICT sector to deliver environmentally sustainable solutions. The largest identified opportunities are: dematerialization; intelligent transport and logistics; intelligent buildings; smart power supply; and efficient industrial processes and systems. This study provides a novel approach into sustainable design in ICT, underlining unsustainable design practices in ICT sector. Review of the literature makes an advance on extant reviews by highlighting the synergic relationship between ICT design, sustainability, and the economy. / +46 704 35 21 35
8

[pt] GERENCIAMENTO DE EMISSÕES DE GASES DE EFEITO ESTUFA DO CAMPUS GÁVEA DA PUC-RIO: INVENTÁRIO DE EMISSÕES E PROPOSTA DE MITIGAÇÃO / [en] GREENHOUSE GASES EMISSIONS MANAGEMENT OF PUC-RIO, GÁVEA CAMPUS: INVENTORY OF EMISSIONS AND A PROPOSAL FOR MITIGATION

03 November 2021 (has links)
[pt] As mudanças climáticas têm sido consideradas por grande parte da comunidade científica como o problema ambiental mais grave já enfrentado pela humanidade. Os estudos conduzidos, ainda que com incertezas, indicam uma forte relação entre as ações antrópicas, o aquecimento global e a consequente alteração climática. Verões mais quentes, invernos mais rigorosos, secas, enchentes, tornados, desertificação, escassez de água, alimentos, perda da biodiversidade são alguns exemplos dos impactos causados por este desequilíbrio. A mitigação ou controle de um problema desta magnitude merece, sem dúvida, atenção dos governos e de empresas responsáveis por grandes emissões de gases de efeito estufa, considerados como responsáveis pela alteração no clima. Entretanto, outros setores também podem e devem contribuir para o alcance das metas globais estabelecidas nos acordos internacionais. O presente trabalho apresenta o resultado de um inventário de emissões de gases de efeito estufa elaborado para o Campus Gávea da PUC-Rio, utilizando-se da metodologia validada pelo Painel Intergovernamental sobre Mudanças Climáticas (IPCC), como ponto de partida para uma proposta de gerenciamento e mitigação das emissões diretas e indiretas do Campus. O estudo ainda indica ações para melhorar a qualidade de inventários futuros e medidas para a redução das emissões. / [en] Climate change has been considered by the scientific community as the most serious environmental problem ever faced by humanity. The studies performed, even with uncertainties, indicate a strong relationship between human actions, global warming and consequent climate change. Hotter summers, colder winters, severe droughts and floods, tornadoes, desertification, water and food scarcity and biodiversity loss are some examples of the impacts caused by this imbalance. The mitigation or control of a problem with this magnitude deserves undoubtedly attention of governments and companies responsible for the large emissions of greenhouse gases, considered as responsible for the climate change. However, other sectors can and should contribute to the achievement of the global targets set by international agreements. Regarding the uncertainties and expectations on climate change, in 1988 the Intergovernmental Panel on Climate Change (IPCC), consisted of scientists from around the world, was created to provide information related to the causes of climate change, its consequences and possible actions to reduce the impact on the earth. IPCC reports are published regularly and become a reference for the formulation of public policies and for use by experts and students. The IPCC in its 4th Assessment Report, indicates a 70 percent increase in anthropogenic emissions of greenhouse gases in the period 1970-2004, where the carbon dioxide (CO2) is the largest contributor. For the same period, CO2 annual emissions increased 80 percent and represented 77 percent of total anthropogenic emissions in 2004. This increase is mainly due to the consumption of fossil fuels and changes in land use. Once established the relationship between greenhouse gases and global warming, it became evident the need for measurement and quantification of emissions for achieving any progress in the management of the problem. For that, a common, standardized, transparent and reliable methodology was desired. Developed in the United States by the World Resource Institute (WRI) in 2001, the GHG Protocol seeks to understand, quantify and manage GHG emissions of companies and nowadays is the most frequently method used worldwide for performing GHG inventories. It is also compatible with standard ISO 14064: 2007 - Greenhouse Gases and the methodologies for quantification issued by the Intergovernmental Panel on Climate Change.

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